title: Effects of FMN riboswitch on antioxidant activity in Deinococcus radiodurans under H₂O₂ stress.
abstract: The flavin mononucleotide (FMN) riboswitch is structured noncoding RNA domains that control gene expression by selectively binding FMN or sensing surrounding changes without protein factors, which are involved in the biosynthesis and transport of riboflavin and related compounds. We constructed the deletion mutant of FMN riboswitch to investigate its possible role in response to H₂O₂ stress in Deinococcus radiodurans. The results showed that the deletion of FMN riboswitch resulted in an obvious growth delay in D. radiodurans. Compared with the survival rate of 56% of D. radiodurans, only 40% of the mutant survived after treated with 50 mM of H₂O₂, indicating that deletion of FMN riboswitch obviously increased the susceptibility to H₂O₂. Compared with the wild type R1 strain of D. radiodurans, FMN riboswitch knockout cells accumulated a higher level of intracellular reactive oxygen species (ROS) while their total catalase activity reduced significantly. Results from quantitative real-time PCR analysis implies structural alterations of in response to H₂O₂ challenge. Our data suggest a critical role of FMN riboswitch in the oxidation tolerance system of D. radiodurans.
authors.affiliation: College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, PR China.
authors.forename: Peng
authors.initials: P
authors.lastname: Yang
authors.affiliation: College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, PR China.
authors.forename: Zhouwei
authors.initials: Z
authors.lastname: Chen
authors.affiliation: College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, PR China.
authors.forename: Zhan
authors.initials: Z
authors.lastname: Shan
authors.affiliation: College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, PR China.
authors.forename: Xianfeng
authors.initials: X
authors.lastname: Ding
authors.affiliation: College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, PR China.
authors.forename: Lili
authors.initials: L
authors.lastname: Liu
authors.affiliation: College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, PR China. Electronic address: jfguo@zstu.edu.cn.
authors.forename: Jiangfeng
authors.initials: J
authors.lastname: Guo
mesh_terms: D000975:Antioxidants / Q000378:metabolism*; D002374:Catalase / Q000032:analysis; D034301:Deinococcus / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D005486:Flavin Mononucleotide / Q000378:metabolism*; D017353:Gene Deletion; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects*; D006861:Hydrogen Peroxide / Q000633:toxicity*; D050296:Microbial Viability / Q000187:drug effects; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000032:analysis; D060888:Real-Time Polymerase Chain Reaction; D058928:Riboswitch / Q000187:drug effects*
chemical_list: D000975:Antioxidants; D017382:Reactive Oxygen Species; D058928:Riboswitch; D005486:Flavin Mononucleotide; D006861:Hydrogen Peroxide; D002374:Catalase
keywords: Deinococcus radiodurans; FMN riboswitch; Oxidative stress